MEDICAL PHYSIOLOGY PHSL 1010:
EXAM 2 2025 QUESTIONSAND
ANSWERS
Depolarizing currents pass to the sarcoplasmic reticulum via: - ANS T-tubules (triads)
The muscle protein that binds to Ca++ during excitation-contraction coupling is: -
ANS Troponin
A skeletal muscle fiber comprises: - ANS One muscle cell only
Fast-twitch muscle fibers differ from slow-twitch fibers in which way(s)? - ANS Slow-twitch
fibers have more myoglobin than fast-twitch AND Slow-twitch fibers are more fatigue-resistant
than fast-twitch
Smooth muscle differs from skeletal muscle in which way(s)? - ANS Smooth muscle cells have
only one nucleus AND Smooth muscle contracts more slowly than skeletal muscle
Smooth muscle dense bodies perform a similar function to: - ANS Z lines (from striated
[cardiac & skeletal] muscles)
Parasympathetic ganglia that aid in control of smooth muscle contraction are located: -
ANS Inside sheets of smooth muscle
The correct sequence of events in smooth muscle contraction is: - ANS Ca++ enters the cell,
Ca++ binds to calmodulin, myosin heads are phosphorylated, myosin binds to actin
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, Cardiac muscle differs from skeletal muscle in which way(s)? - ANS Cardiac muscle cells have
only one nucleus and are branched
Intercalated disks: - ANS Both serve as the insertion point for cardiac muscle cells and
contain numerous gap junctions and desmosomes
Excitation-contraction coupling in cardiac muscle: - ANS Is both limited by parasympathetic
activity and is similar to that seen in skeletal muscle
Action potentials in cardiac muscle cells: - ANS Are characterized by a broad plateau as Ca++
enters the cell
Depolarizing signals pass through the atrial musculature via: - ANS Gap junctions
The first "heart sound" is made by: - ANS Closure of the mitral valve AND Closure of the
tricuspid valve
The greatest blood pressure is achieved at: - ANS Atrial diastole
Papillary muscles: - ANS Anchor the leaflets of the A-V valves AND Are inserted into the
ventricular musculature
Cardiac output: - ANS Varies with heart rate (and stroke volume)
The Frank-Starling Law of the Heart shows that cardiac muscle: - ANS Achieves maximum
force when muscle fibers are stretched AND Achieves maximum force when end diastolic
volume is greatest
Contractility of the heart: - ANS Can be enhanced by catecholamines
2 Copyright ©2025 BRAINBARTER ALL RIGHTS RESERVED
EXAM 2 2025 QUESTIONSAND
ANSWERS
Depolarizing currents pass to the sarcoplasmic reticulum via: - ANS T-tubules (triads)
The muscle protein that binds to Ca++ during excitation-contraction coupling is: -
ANS Troponin
A skeletal muscle fiber comprises: - ANS One muscle cell only
Fast-twitch muscle fibers differ from slow-twitch fibers in which way(s)? - ANS Slow-twitch
fibers have more myoglobin than fast-twitch AND Slow-twitch fibers are more fatigue-resistant
than fast-twitch
Smooth muscle differs from skeletal muscle in which way(s)? - ANS Smooth muscle cells have
only one nucleus AND Smooth muscle contracts more slowly than skeletal muscle
Smooth muscle dense bodies perform a similar function to: - ANS Z lines (from striated
[cardiac & skeletal] muscles)
Parasympathetic ganglia that aid in control of smooth muscle contraction are located: -
ANS Inside sheets of smooth muscle
The correct sequence of events in smooth muscle contraction is: - ANS Ca++ enters the cell,
Ca++ binds to calmodulin, myosin heads are phosphorylated, myosin binds to actin
1 Copyright ©2025 BRAINBARTER ALL RIGHTS RESERVED
, Cardiac muscle differs from skeletal muscle in which way(s)? - ANS Cardiac muscle cells have
only one nucleus and are branched
Intercalated disks: - ANS Both serve as the insertion point for cardiac muscle cells and
contain numerous gap junctions and desmosomes
Excitation-contraction coupling in cardiac muscle: - ANS Is both limited by parasympathetic
activity and is similar to that seen in skeletal muscle
Action potentials in cardiac muscle cells: - ANS Are characterized by a broad plateau as Ca++
enters the cell
Depolarizing signals pass through the atrial musculature via: - ANS Gap junctions
The first "heart sound" is made by: - ANS Closure of the mitral valve AND Closure of the
tricuspid valve
The greatest blood pressure is achieved at: - ANS Atrial diastole
Papillary muscles: - ANS Anchor the leaflets of the A-V valves AND Are inserted into the
ventricular musculature
Cardiac output: - ANS Varies with heart rate (and stroke volume)
The Frank-Starling Law of the Heart shows that cardiac muscle: - ANS Achieves maximum
force when muscle fibers are stretched AND Achieves maximum force when end diastolic
volume is greatest
Contractility of the heart: - ANS Can be enhanced by catecholamines
2 Copyright ©2025 BRAINBARTER ALL RIGHTS RESERVED
